Facebook left horrific Islamic State videos on its site for three years, the Daily Mail can reveal.

Despite repeated criticism of the social media giant for failing to protect users, the infamous Cubs Of The Caliphate film posted in March 2015 was one of several that could still be viewed until last week.

Facebook claims to have cracked down on hate content but the video and other sickening IS propaganda was not removed until a detailed complaint from the Mail. Thousands of users have watched the video, which shows a young boy – pictured – shooting dead a teenage hostage.

Other IS material which was on Facebook for over two years includes masked terrorists carrying out mass beheadings of Christians and knifemen warning: ‘You will not have safety, even in your dreams, until you embrace Islam.’

A bomb tutorial used by Manchester Arena bomber Salman Abedi was repeatedly uploaded.

Experts fear there is a deliberate attempt to use Facebook to target potential British jihadi recruits. Former UK counter-terrorism chief Sir Ivor Roberts said the failure to take down the videos was ‘chilling and inexcusable’.